Fluid filters are widely known and used in various filtration systems and applications, for instance where there is a need for particle and/or fluid separation from a working fluid in a protected system. As one example, fuel filtration systems for engines are well known and can employ fluid filters that are aimed at water and particle separation from fuel. Filter cartridges in some of these filters have one filter element with media to first coalesce water, and have another filter element that has media to further filter the fuel, while the coalesced water drains from the cartridge. In many cases, such media is arranged in a concentric filter within a filter configuration, where the outer filter element has the more coarse media to coalesce the water, and the inner filter element has the more fine media that can remove particulates from the fuel, while the coalesced water drains out of the cartridge.
However, current filter within a filter designs can encounter problems. Avoiding problems is desired to provide effective filtration, to provide water removal efficiency, and to protect engine components.
Improvements can be made upon existing filter designs. Particularly, structural improvements can be made as to how cartridges having the filter within a filter arrangement are sealed, so as to prevent a working fluid from bypassing the outer filter element of the cartridge before reaching an inner filter element of the cartridge.